From time to time I've a DSL that will not reach either the lan or the internet. Upon such time a backup hotspot is configured:

replacing

/boot/loader.conf
/etc/firewall-ipfw
/etc/firewall-pf
/etc/rc.conf

and maybe one other file...
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copy four to ethernet > wifi
copy five for wifi > ethernet (resolv.conf )
something in the sysctl AND pf script I've run to start the latter
breaks the wifi at least for now
bootup =to= wifi *stable* is fragile here, but working fine. Which
is why I'd like to see some frontend that could resolve setup
problems and not a reboot, eventually.
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As a side complaint, the DSL modem, that is newer, is less
informative as to if it can do internet via the lites on its
front edge, and they are smaller to boot. Proprietary to
the DSL provider, so little use complaining there.
.......................

They each have to be triply-checked in case the USB wlan0 is
changed (bwn0 > run0 ) (run0 > rum0) etc... and in some
instances re-edited

The usual copies have to be backup up before replacing of those
four or five files
Then a reboot, can obtain a lease, a majority of the time, from the
hotspot, the desktop can be started, and a small shell script run
from an xterm so that the wifi stays up more reliably.

This obtains about seventy percent of the speed of the DSL connection
and I usually can resolve the latter within a day or so.

Just writing this scenario in a post so that someone has examples of
a best practice with regards to the situation, or better yet can provide
some hint of a shortcut to the time it takes.
[1]

I've small shell scripts to changeover the files, however in this instance,
I found them to be obsolete, having been written several years ago
and changes to files/drivers in both the usual file set and the replacement
file set means a triple-way editing of them all to again be in sync.

[1] Actually writing it though, in case some base binary eventually appears
to facilitate the switch... sounds like a lot of work but would make
an internet connection more likely for first-time users, being more
user-friendly in some, not all, of new setup configurations POSSIBLY
not at first... sounds like a lot of coding and testing, not so much in the
former if network expertise is present...

[2]
someone may actually have a failover already configured in a shell
script, for a company-wide or building-wide internet connection, and
can give clues in that regard even if it involves purchasing additional
hardware or the creation of a better network topology.

Well, the DSL is back up... I, while the wifi was active, crafted a .zsh to switch back to an ethernet from a USB stick connection, [replacing 5 files] worked the first time. A backup disk meanwhile on a separate IFCONFIG .N, and disconnecting/reconnecting/rebooting lan/router etc, might have solved it today, or what the upstream DSL did yesterday might have solved it. They did not say.
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At any rate the downtime got two .zsh ( wired > wifi ) (wifi > wired) crafted, at least
the latter works fine. So there is that.
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In other news, one can have PF and IFPW working simultaneously, which one might
have inferred from this thread. I've the latter as default and the former started after login.
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